Chosen Solution

The LG logo appears very briefly, then the screen goes black. Sound seems to work fine. Unable to pull up any settings or menus. (This has happened before) Update (09/18/2016) LG 50LN5600 55" smart tv Less than 2 yrs old No storms of any significance

@shnovy start off by measuring a few voltages from the power board to the main board. Let us know what you get on that.